Poor Idle on a 1150 Merc. 1971

[Scot-a-lot]

I have a poor idle, seems to be a common problem. When the motor is in neutral, the motor will run well if the rpms are medium to high and if I shut it off while it is running, it is easy to start. If I let the idle drop low, the motor will eventually stall and will not restart until I pump the bulb well. Good spark, new plugs, new gas lines, carbs rebuilt. What else would cause this? How can I narrow down the problem?

 

[mrm]

Re: Poor Idle on a 1150 Merc. 1971

I would check the timing.<br /> MRM

 

[mrc]

Re: Poor Idle on a 1150 Merc. 1971

I'm not a mechanic, but I did stay at holiday inn <br /><br />Something to have checked is the crankcase vacuum.<br />(The other half of the compression check you do<br />on a cylinder/piston.<br /><br />Mike

 

[Scot-a-lot]

Re: Poor Idle on a 1150 Merc. 1971

is there a way to test the crankcase pressure?

 

[Scot-a-lot]

Re: Poor Idle on a 1150 Merc. 1971

Anyone have an idea about this one? How can I check the vacuum pressure?

 

[Scot-a-lot]

Re: Poor Idle on a 1150 Merc. 1971

anyone?,.....anyone?....